Abstract

To the Editors: Demers and colleagues (1) reported on the prevalence of thrombosis in antithrombin-III-deficient patients. They analyzed 31 patients from a large kindred and another 449 patients from 62 kindreds described in the literature. All had antithrombin-III quantitative deficiency or impairment in serine protease inactivation; families with isolated disturbance in heparin binding were not included. The pooled prevalence of venous thrombosis was found to be 51%.

We analyzed 552 patients affected with (n = 344) or at high risk (0.5) for antithrombin-III deficiency (n = 208) and belonging to 40 different kindreds. Of 120 recorded deaths, 44 (36.7%) were